I started to do that, but i stopped myself with the logic that if i have to dial them back more than a click or two, then two subs is too much to begin with. At $1100 each (december discount), i couldnt see not utilizing their full potential.
Listening to multichannel or stereo music, which rarely got the X13's even started (probably zero content below 40Hz) was a giant waste of money. The first Master Audio 7.2 Bluray i played had a constant overpowering hum of bass energy in normal scenes that have an underlying sense of shits-going-to-happen soon ! It made the movie unwatchable, but when that storm did hit, it about blew the walls out of my room !! The same scenes with just one X13 was far more enjoyable and the big hits were still major impressive, whilst saving my wall studs !
I worked with the two X13s for a few days but the room is just too small. These things are strong !